As a healer, I'll take your side 100% of the time. DPS shouldn't pull, nor should they instantly attack a spread out mob from a group the tank hasn't fully taunted yet. It's always irritating to see a DPS pull unexpectedly then blame me for dying.
Pretty much this. Marauders seem to be the worst offenders for jumping right into a fight, and ya, as a tank, I generally don't bother helping when they do that, and as a healer, same deal.
Even had one tank who insisted on doing all the little bonus crap on HM Foundry even though I asked him not to because I had to leave very shortly. Needless to say I didn't try too hard to keep him alive. I basically let him hover between 20-60%hp for the remainder of the flashpoint.